Method of making drills or the like



JOHN J'. KUNZER, 0F CHICAGO,

ILLINOIS, AssIGNOn rro OF CHICAGO, ILLINOIS, A CORPORATION JOSEPH T. nYEnsON a SON, or ILLINOIS.

METHOD or MAKING nRILLs on T IIE LIKE.

Specification of Letters Patent.

Patented May 31,1921.

Application led. May 4, 1918.' Serial No. 232,477.

To all 'w/Lom t may concern:

Be it known that'I, JOHN J. KUNZER, a

citizen of the United States, and a resident` of Chiago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Methods of Making Drills or the like; and I dohereby declare that the following is a full, clear,

and eXact description thereof, reference be-l tives, drilling gun barrels, and the like, and

the object of the invention is to provide a novel method for producing drills orlike Cutting tools equipped with a longitudinali duct or ducts through which a cutting compound is fed under pressure to the cutting end of the tool, both for the purpose of lubricating the cutting end of the tool to maintain it suitably cool and to furnish means for flushing out the chips fromthe cutting end of the tool backwardly through a longitudinal flush channel or channels of the tool and to thereby prevent thehole being drilled or otherwise cut from becoming clogged. i A v In the following description my invention is described with particular reference to deep drilling, but'it will be understood that the invention may be exemplified in or in connection with other cutting tools such as reamers or the like..

Drills for deep drilling work arerequired to be made of considerable length, with respectto their diameters, and it is also necessary that said drills be made of great strength, to avoid twisting of the drill under the torsional stress imposed thereon.

In order that a drill for this purpose may be sufiiciently sturdy to withstand the stresses imposed upon it in this work, it desirable that the drill be made of a continuous piece of steel or like material, by which is intended to include a drill .having a specially hardened bit or cutting end welded to the shank or bar of the drill or wherein the entire drill is made of the saine perse,

material, with the cutting end properly tenidf In drills of the smaller sizes, as,I for instance', from fig practicable to drill a Yduet fora cutting conipound throughout the length ofthe drill; and even in larger drills of considerable length the drilling of such duct'is attended with considerable difficulty.

Itis the purpose ofthe present invention inch and smalleig'it is not to provide -a method of making drills with longitudinal cutting compound ducts in suchV a Way that it is practicable Vto produce such drills of diameters heretofore not possible and also -to more readily produce such cutting compound ducts in larger drills.

In accordance with my novel method of Y producing drills, a bar of any suitable or preferred cross section, and of the proper length, is longitudinally grooved to a suit-V able depth, either by being originally formed with a groove, as by a rolling, swag ing, drawing or eXtruding process, or by a subsequent milling operation, the groove-ei'- tending to and opening at the cutting end orbit of the drill.

After the slot has been completed, arfilling strand of any suitable material, such'. as

Saidv groove' may be made of any particular cross section desired.

steel, is laid in the groove. Thereafter the Y portion of the groove exterior to the strand is filled with a metal suitably applied so as to be permanently held therein and to constitute part of the drill bar. Said metal may be ofv a character which is capable ofbeing welded, brazed or otherwise bonded to the metal of the drill at the sides of the groove, or the filling metal may be pressed, hammered, or rolledV into the groove under heavy pressure. After thefilling metal has been applied, the strand may be withdrawn endwise from the slot, thereby leaving a duct in the drill of a diameter slightly greater than the exterior diameter of the y strand. If the strand be hollow itmay reduct for the cutting fiuid. I

The material by which the groove exterior tothe duct forming strandV is filled nia-y be applied in a molten state andcaused to be formed therein and welded or bonded to the sidev walls of the groove. The mate--v main in the slot of the drill to constitutethe rialV when ,thus applied to fill the 'groove may be fused either by an velectrical or flame fusing method. i

W lienztheinateri'al is ap'piied in, a molten' Y,

state, means are provided for preventing the welding or bonding heat of the filling material from overheating or melting the material ot the duct Jforming strand dun ing the welding or bonding operation. rllhis may be effected by covering the duct torming strand with a coating of heat insulating material, such, for instance, as asbestos, or may be effected by producing continuous relative endwise movement of the strand and drill during the time the slot is beingthus lled.

The insulating coating, when employed not only serves to thus protect the strand trom overheat, but also, by its presence, offers sufficient freedom of movement to the strand, when the filling material has cooled) to permit the strand to be drawn endwise from the slot, thus leaving a longitudinal duct ot the desired diameter in the drill bar.

lt a continuous endwise relative movement of the strand and drill be maintained while the groove is being thus filled, the strand does not become overheated in any one place to an extent to cause itrto be softened by the welding, brazing or bonding heat. There fore, the strand does not bind against the walls oit the groove or stick therein.

Such relative end wise movement of the strand and drill will also be maintained when the lil ling metal is pressed, hammered, or rolled into the groove, so as to thereby prevent the strand being` compressed in the groove in such manner as to malte its subsequent withdrawal difficult or impossible. This relative endwise movement of the strand and drill may be effected by moving either ot the parts with respect to the other. lWhen the strand is moved, any suitable method may be employed for thus continuously moving it in the groove. For instance, the strand may constitute a portion of an endless wire which may be trained -over and continuously driven by suitable means in one direction or the strand may be reciprocated in any suitable manner through the Af roove.

A drill may be thus provided with one longitudinal duct or with two parallel ducts, or said drill may be provided with single longitudinal duct opening at the cutting end of the drill. and provided at the cutting` end ot the drill with a shorter oblique duct which opens also at the cutting end oi"- the drill and intersects the longer duct, The said duct or ducts may be made by continu-- ingthe groove or grooves to the cutting end of the drill, or the groove or grooves in which the duct forming strands are laid may be discontinued short oi" the end of' the drill bar and the duct or ducts at .sa-id cuttingend formed by drilling openings, which aline with said grooves.` By so drillingthe duct or ducts at the cutting end oftheV drill, the cutting bit or bits are not subjected to the invasor.

welding, brazing or bonding heat of the groove illing material when the mate 1ial is applied in a manner to be thus secured to the drill.

rlhe drill is completed by forming one or more longitudinal chip clearance grooves therein. When the drill bar is rectangular such chip clearance grooves, except at the cutting end of the drill may not in some instances be required.

ln the drawings are illustrated a number or" modifications of drills constructed in aecordance with the novel method herein disclosed wherein the groove is closed by applying the filling metal in a molten state, and in the following detailed description, reference is made to this specific phase of the process. lt will be understood, however, that said method may he adapted to other specific types of deep drills, Vwithin the spirit and scope ot the invention, and, "further, that the groove filling material may be applied to and formed in the groove by the pressure method set forth in my application for United States Letters Patent Serial Number 248,724 filed on the seventh day oi? August, 1918.

As shown in the drawings,

Figure l is a broken plan view of a showing in different portions of its leng different stages of the method of producing the longitudinal cutting fluid duct therein.

Figs. 2, 3, and 4 are cross sections on the lines 2-2, SMS, and 4-4 of Fig. l.

Fig. 5 is a broken side elevation, showing another modification.

Fig. 6 is a cross section on the line (3-6 Fig. 5.

Fig. 7 is a broken side elevation of a drill, showing a urther modification.

Fig. 8 is a cross section ot a. cylindric drill bar, showing one method of finishing the drill. i

Fig. 9 is a perspective view of a hirthlr modiiication.

Fig. l0 is a modilication, showing a still further modification.

Fig. ll illustrates one means of continuously moving the duct forming strand in the groove during the welding or bon-'ling operation.

As shown in Fig. l. l0 designates the drill as a whole and 'll designates its cutting end or bit, the latter to be made ot' any proerred or desirable form. The drill shown in Fig. l is cylindric, its cross section being indicated in Figs. 2, and 4. Said drill is provided with a longitudinal chip clearance groove 12.

ln Fig. 2, and also near the cutting end of the drill, is shown the groove i4 to receive the duct forming' strand, said groove being formed in any suitable manner. lt may be made of any preferable cross section. or dimansion.,

finir o In Fig. 3, and at the corresponding portion of Fig. 1, is designated the duct forining strand l5, preferably consisting of a steel wire of proper diameter 'to the bottom of the groove.' vThe cross section of said strand and the consequent cross section of the groove may be varied as desired to produce a resultant duct of a preferred cross section.

In Fig. d, and at the corresponding portionof Fig. 1, i6 designates the body of metal which fills the groove 1a exterior to the duct forming strand. This body of metal may be applied to the slot in a molten stateand welded or bonded to the side walls of the slot, or the filling materia-l may be otherwise applied and fixed to the metal of the groove wall. During thetime the groove is being thus filled the strand 15 maybe protected from overheating by a coating of insulating material, or `'said strand may be kept continuously in motion, as by the means illustrated in Fig. 11. Als' shown in said F ig. 11, the-strand may be attached'at one end to hand piece 17 `andmay be attached at its other end to a weight 18, the strand being trained between the weight and the drill bar over a slieave 19. During theA time the groove is being filled with the molten metal or during the time the welding, brazing or bonding heat is applied, or during the time the pressure is applied to the filling material to. force and finit in the groove, as set forth in my aforesaid application, the strand may be pulled endwise in one 'direction by the rhandle 17 and, when pulling stress on said handle is released, pulled in the other direction by the weight 18. Other eans to maintain the strand in motion may be employed. i Y

After the groove has been thus filled the drill bar may be peripherally finished to cut awayv any portion of the groove filling metal which may project beyond its periphery and to also provide the required drill clearance along the bar. n

InYV some instances the bar may be originally made of greater diameter than the finished drill, as illustrated by the dotted eccentric outline in Fig. 8, and the metal of the bar included between dotted and full outline cut away to produce the desired clearance. In this event the said bar mayY be finished about an axis eccentric to the aXis of the original bar, so aspto thereby avoid cutting away any appreciable thickness of the groove filling material. Y

rEhe drill shown in Figs. 5 and 6 is pro-V vided with two ducts 21 and may be provided with two chip clearance grooves 22.V

In this construction the said ducts may be located at opposite sides of the aXis of the drill bar,'or otherwise, and the chip clearance grooves may be likewise symmetrically disposed., The two ducts and clearance grooves may be employed in connection with a double lipped cutting end 23, each duct opening near each cutting lipA or bit.

In the drill shown in Fig. 7 a single longitudinally disposed duct 2e is provided which f communicates, near the double lipped cutting end 23 with an oblique duct 25 which extends to and opens at one of the cutting lips of the drill, .the main duct 2lexten'ding toV vand opening at the other cutting' lip. In this construction the drill may be provided with two longitudinal chip clearance one of which is'shown in Fig. 7.

VIn Fig. 9 a drill bar of rectangular cross section is shown. Insaid Fig. 9 two ducts 27 are provided in connection with two cutting lips; said' ducts being located on opposing side faces ofthe `drill bar. In this construction the flat faces ofthe drill bar, which meet at anglesat the corners of the drill where the drill coincides with the circus lar hole which it cuts, may provide the necessary chip clearance channels without the grooves 26, Y

necessity of providing'clearance grooves therein, asin the'cylindric drills. The two opposed sides of the rectangular drill bar at the cutting endl thereof may be provided adjacent to the cutting lips withshort clear ance recesses 28, depending -upon the cross section of the bar, which, rearwardly from said cutting lips,merge into the sides of the drill bar.

In some instances, the cutting endvof the drill may be made of va harder steel than the remainder of the drill bar and welded to the bar, as, for instance, at'the point indicated by the line 29 in Fig. 7. 'It will be observed, however, that the drill barn in each instance is madeof acontinuous piece of materialV of such'character and of such rugioo gedness as to withstand the severe work r imposed thereon in deep drilling.

In the construction shown in F1g.'10, the

cutting compound'duct is formed partially by the groove and filling method before described, and partially by Ldrillinga duct 30 through the body of the cutting end of the n drill bar. In suoli instance, the groove to receive the duct forming strand is termi# nated short of the cutting end, and the duct 8O drilled in said cuttingend to aline with ,said groove. An advantage of this construction is that the cutting end or bit ofthe drill is not subjectedA to the welding, braz-Y ing, or bonding vheat of the material to fill thegroove." j` t Both ends of the drill be formed to provide drill bits or lips .2.37 asl shown: Vin inl whichv event the chip clearance groove` or grooves 26 are extended from `and to the endof the drill.` In such construction the drill may be made somewhat longer than Y a single hit drill so as to provide the necessary clearance Vfor the required depth of drilling.l In such a drill', after one end of izo the drill has been worn away by continued sharpening to the clearance diameter of the shank or bar, the drill may be reversed to likewise use the other end thereof.

Reference in the specification and claims to drills is not intended to restrict the invention to drills in the limited sense of that term, but is intended to include all similar tools such as reame-rs, threaders, or the like, where similar working conditions obtain.

I claim as my invention:

l. The improved method of making drills having longitudinal lubricating' ducts, which consists in inserting a longitudinal duct forming strand in the body of the drill, and thereafter covering the strand with a metal filler.

2. The improved method of making drills having longitudinal lubricating ducts, which consists in laying a duct forming Strand in a longitudinal groove of the drill bar and thereafter filling said groove and welding 0r bonding the filling material to the walls of said groove and effecting relative endwise movement of the strand and drill bar during the filling operation.

3. The improved method of making drills having longitudinal lubricating ducts, which consists in laying a duct forming strand in a longitudinal groove of the drill bar, thereafter filling said groove with a metal filler and fixing the filler metal therein, and nally withdrawing the duct forming strand.

4:. The improved method of making drills having longitudinal lubricating ducts, which consists in laying a duct forming strand in a longitudinal groove of the drill bar, thereafter lling said groove and welding or bonding the filling material to the walls of said groove, and finally withdrawing the filling strand.

5, The improvement in the method of making drills having longitudinal lubricating ducts, which consists in longitudinally grooving the drill bar, laying a duct forming strand in said groove, and thereafter filling said groove and effecting relative endwise movement of the drill bar and strand during the filling operation.

6. rlhe improved method of making drills having longitudinal c lubricating ducts., which consists in longitudinally grooving the drill bar, laying a duct forming strand in said groove, filling the remaining portion of said groove, and thereafter withdrawing the filling strand from said groove.

7. The improved method of making drills having longitudinal lubricating ducts,

which consists in laying a duct forming strand in a longitudinal groove of the drill bar, thereafter filling said groove with a nsvaeea molten material and fixing it to the walls of the groove, and protecting said strand from sticking in the groove during the welding or bonding operation.

8. rllhe improved method of making drills having longitudinal lubricating ducts, which consists in laying a duct forming strand in a longitudinal groove of the drill bar, thereafter filling said groove with a molten material and welding or bonding it to the walls of the groove, and protecting said strand from overheating during the welding or bonding operation.

9. The improved method of making drills having longitudinal lubricating ducts, which consists in laying a duct forming strand in a longitudinal groove of the drill har, thereafter filling said groove with a molten material and welding or bonding it to the walls of the groove, and continuously moving the strand in said groove during the welding or bonding operation.

10. rlhe improved method of making drills having longitudinal lubricating ducts which consists in laying a duct forming strand in a longitudinal groove of the drill bar, filling said groove with a molten material and welding 0r bonding it to the walls of the groove, protecting said strand from overheating during the welding operation, and thereafter withdrawing the strand endwise from said groove.

l1. The improved method of making drills having longitudinal lubricating ducts which consists in laying a duct forming strand in a longitudinal groove of the drill bar, thereafter filling said groove with a molten material and welding or bonding it to the walls of the groove, continuously moving the strand in said groove during the welding operation, and thereafter withdrawing the strand endwise from said groove.

l2. |The improved method of making drills having longitudinal lubricating ducts which consists in laying a duct forming strand in a longitudinal groove of the drill bar, thereafter filling said groove, thereafter removing said strand, and finally peripherally finishing said bar.

13. 'llhe improved method of making drills having a longitudinal lubricating duct which consists in enveloping a longitudinal duct forming strand in the body of the drill, withdrawing said strand to leave a duct in the drill bar, and drilling a duct through the cutting end of the drill which communicates with the duct thus formed.

In testimony whereof l claim the foregoing as my invention, l hereunto append my signature at Chicago, illinois, this A29th day or April, i918.

Y JOHN J. Korman. 

